Caution: Always unplug first. Also, an electrical charge of several thousand volts can be retained by various parts within the protective cabinet long after power has been removed. After a faulty part has been replaced the set should be tested for proper and safe operation.
Televisions are still among the most complex devices that exist and only well trained and highly skilled personel should attempt even the replacement of a fuse. An improperly operating television can emit harmful X-rays.
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